The invention is directed generally to an auger assembled from a plurality of auger segments and, more particularly, to a plurality of auger segments, each of which is made of an inert material and has end-for-end symmetry, assembled end-to-end about a drive shaft to comprise an auger.
Augers are widely used for the linear transport of fluids and fluid-like materials, such as water, sludge, sewage, grain, coal, and the like. Augers present a substantial surface area that comes into contact with the material being transported. Moreover, the rotational motion of the auger causes the exposed surfaces of the auger shaft and flighting to contact and be abraded by the transported material. The life of the auger, accordingly, is dependent upon the abrasion and corrosion resistant properties of the exposed surfaces of the auger. Augers having flighting and other exposed surfaces made of high-density plastics, such as polyethylene, have both excellent corrosion and abrasion resistances. One-piece augers made from such materials are known in the prior art.
Articles made from a high-density plastic like polyethylene are typically manufactured by plastic injection molding. This manufacturing process requires a specially constructed mold to be created for each length of auger to be constructed. The creation of such molds is an expensive capital cost of the injection molding process. The cost of augers produced by injection molding can be reduced by reducing the number of different molds required in the manufacturing process.
When damaged, conventional metal augers may be repaired by the reconstruction or replacement of damaged flighting by means of welding, brazing, or the like. Plastic augers, however, are not easily reconstructed or repaired and damage to a small section will frequently require the replacement of the entire auger length.
The auger segments of the present invention eliminate these problems by permitting the assembly of augers of discrete lengths by the use of the appropriate number of auger segments assembled on a main shaft in an end-to-end and mating relationship. The individual auger segments possess end-for-end symmetry and can be manufactured from a single plastic injection mold. If an auger constructed of these auger segments is damaged, the auger can be easily and economically repaired by the replacement of the auger segments that were damaged. Polyethylene augers constructed of auger segments of the present invention have been found to be economical of construction and long-lived when used in extremely corrosive and abrasive environments such as the handling of animal wastes and granular fertilizers.